I'm not sure that is worth the time(re gelcoat removal
and replacement). We've a customer right now who just bought a uniflite(valiant manufacturer) that had everything above the rub rail re-gelcoated at great expense. Means the most recent blisters are nice and shiny...
If it were mine I'd use the same thing we're doing. Cut open with a sharp knife. Quick solvent wash, scuff sand, fill with a tinted to match existing gel coat polyester mix(polyester resin with a bit of gelcoat
added and a little filler too, though I'm not sure which type.) When filling use a plastic putty knife. If you want to get fancier, a light spray with a preval evens it out ok since the mix is already part gel coat and already colored close to correct.
Not the prettiest at 6", but 6' away it's close enough even without a spray of gelcoat. Best treated as a maintenance
item I think unless you want to go all the way for other reasons like gel coat is worn through and damaged elsewhere.
The previous owners bill was most unpleasant after re and re of all hardware
, spraying, buffing etc. Quite close to what our customer paid for the boat if I remember correctly.